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991.
Disagrees with J. C. Wakefield's (see record 1987-28660-001) argument that 2 kinds of sex bias, logical and factual bias, may influence the diagnosis of primary orgasmic dysfunction in women and suggests that instead of bias, there may be errors in the diagnostic criteria. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The Arabidopsis thaliana UBC7/13/14 genes encode a family of multiubiquitin chain-forming E2 enzymes
Covalent modification of proteins by attachment of multiubiquitin chains serves as an essential signal for selective protein degradation in eukaryotes. The specificity of ubiquitin-protein conjugation is controlled in part by a diverse group of ubiquitin-conjugating enzymes (E2s or UBCs). We have previously reported that the product of the wheat TaUBC7 gene recognizes ubiquitin as a substrate for ubiquitination in vitro, catalyzing the condensation of free ubiquitin into multiubiquitin chains linked via lysine 48 (van Nocker, S., and vierstra, R. D. (1991) Proc. Natl. Acad. Sci. U. S. A. 88, 10297-10301). Based on this activity, this E2 may play a central role in the ubiquitin proteolytic pathway by assembling chains in vivo. Here, we describe the cloning and characterization of a three-member gene family from Arabidopsis thaliana (designated AtUBC7/13/14) encoding structural homologs of TaUBC7. Like TaUBC7, recombinant AtUBC7/13/14 proteins formed multiubiquitin chains in vitro. AtUBC7/13/14 mRNAs were found in all tissues examined, and unlike related UBCs from yeast, the levels of mRNA were not elevated by heat stress or cadmium exposure. Transgenic Arabidopsis were engineered to express increased levels of active AtUBC7, for the first time altering the level of an E2 in a higher eukaryote. Plants expressing high levels of AtUBC7 exhibited no phenotypic abnormalities and were not noticeably enriched in multiubiquitinated conjugates. These findings indicate that the in vivo synthesis of multiubiquitin chains is not rate-limited by the abundance of AtUC7 and/or involves other, yet undefined components. 相似文献
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T Kohmoto PE Fisher A Gu SM Zhu OJ Yano HM Spotnitz CR Smith D Burkhoff 《Canadian Metallurgical Quarterly》1996,61(3):861-868
BACKGROUND: Early reports indicate that transmyocardial laser revascularization improves symptoms in patients with refractory angina. However, there is little experimental evidence of whether blood flow through channels is the mechanism of action. METHODS: Endocardial channels were made in the distribution of the left anterior descending coronary artery in canine hearts (n = 5) using a holmium:yttrium-aluminum garnet laser. Hearts were excised acutely while perfused in a retrograde fashion from a second dog so that the aortic valve always remained closed. The proximal left anterior descending coronary artery was ligated. To measure direct transmyocardial blood flow, colored microspheres were injected into the left ventricular chamber. RESULTS: The number of spheres per gram of tissue in the channel region was significantly higher than in the control region (low load, 302.5 +/- 169.0 versus 41.8 +/- 59.4; high load, 208.4 +/- 138.3 versus 5.8 +/- 11.7; both, p < 0.05). However, the estimated regional blood flow through the channels was extremely low (<0.01 mL/g/min. In the chronic setting (n = 4) (2-week survival), no flow as detected through the channels, and the endocardial entry points were closed. CONCLUSIONS: Transmyocardial blood flow does not appear to occur through channels made with the holmium:yttrium-aluminum garnet laser. It remains to be determined whether this is the case with other types of lasers. 相似文献
996.
The trend toward the use of composite materials and digital electronics has renewed the need to quantify the effects of lightning strikes to airplanes, since composite structures do not provide shielding equivalent to that of metal aircraft, and digital systems are potentially more susceptible to upset by electrical transients than are analog electronic systems. A research program, called the Storm Hazards Program, has been run by the National Aeronautics and Space Administration (NASA) for the past eight years and has provided the first statistically significant measurements of the electromagnetic interaction between lightning and aircraft. A NASA-owned F-106B airplane has been flown through thunderstorms about 1500 times at altitudes between 5000 and 40000 feet (1500 to 12000 meters). The airplane, lightning-hardened and outfitted with special instruments, was hit by lightning 714 times. The types of measurements made and the results are described. The Storm Hazards Program has concluded, and interpretation of the data gathered is underway 相似文献
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MK Popkin AL Callies EA Colón RD Lentz DE Sutherland 《Canadian Metallurgical Quarterly》1993,34(3):251-258
To examine the role of psychiatric diagnosis in the surgical outcome of pancreas transplantation, we studied candidates with type I diabetes mellitus. Eighty of 140 candidates underwent transplantation. Survival analysis found the extent of human leukocyte antigen-DR (HLA-DR) matching, two diagnoses, and patients' perceived support from first-degree relatives to be related to duration of full-graft function. Lifetime diagnoses of tobacco use disorder (P = 0.029) and alcohol abuse/dependence (P = 0.006) were associated with less favorable outcomes; perceived support was associated with positive outcomes (P = 0.048). Subsequent analysis suggested that the four variables independently and directly affect outcome. 相似文献
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